Wireless communication system, base station apparatus, mobile station apparatus, and communication method

ABSTRACT

To perform MBMS transmission capable of effective utilization of resources without increasing load in a mobile station apparatus. In a wireless communication system including a base station apparatus and mobile station apparatuses to provide an MBMS (Multimedia Broadcast Multicast Service), the base station apparatus transmits a message for aggregating the number of mobile station apparatuses requesting an MBMS to a mobile station apparatus being served, and, among the mobile station apparatuses, the mobile station apparatus requesting an MBMS adds intra-cell location information of its own to a response message to the message and transmits the response message added with the intra-cell location information to the base station apparatus.

TECHNICAL FIELD

The present invention relates to a wireless communication system, a basestation apparatus, a mobile station apparatus, and a communicationmethod which perform communication using a plurality of subcarriers, andparticularly to a communication method of an MBMS (Multimedia BroadcastMulticast Service).

BACKGROUND ART

Evolved Universal Terrestrial Radio Access (hereinafter referred to asEUTRA) which has evolved the third generation mobile communicationsystem in the 3GPP (3rd Generation Partnership Project), and AdvancedEUTRA (also called LTE-Advanced, and hereinafter referred to as A-EUTRA)which is a further development thereof are under study (see Non-patentdocument 1).

FIG. 12 illustrates an exemplary configuration of a downlink radio framein EUTRA. In FIG. 12, a radio frame is shown with the time axis beingthe horizontal axis and the frequency axis being the vertical axis. Aunit of the radio frame is composed of dividing the frequency axis into12 subcarriers (sc) and the time axis into slots which are aggregates ofa plurality of OFDM symbols, and a region partitioned by 12 subcarriersand one slot length is referred to as a resource block. A set of twoslots is referred to as a subframe, and a set of 10 subframes isreferred to as a frame. A plurality of resource blocks is contiguouslyarranged in the frequency direction, with 100 resource blocks beingarranged in a bandwidth of BW=20 MHz. A guard band in which no signal istransmitted is provided at both ends thereof to prevent radiation toadjacent bands.

As indicated by the explanatory note in FIG. 12, the subframes 0# and 5#each include a primary synchronization channel (P-SCH) used forsynchronization with the base station, a secondary synchronizationchannel (S-SCH), and a primary broadcast information channel (P-BCH).The mobile station apparatus establishes frame synchronization usingP-SCH and S-SCH, and also specifies a physical cell ID (PCI: PhysicalCell Identification) for identifying the base station apparatus. Inaddition, the mobile station apparatus acquires main parameters such asthe number of transmitting antenna ports by demodulating broadcastinformation (MIB (Master Information Block)) included in P-BCH, andacquires other broadcast information from a dynamic broadcast channel(D-BCH) provided in a downlink shared channel (DL-SCH). The broadcastinformation included in D-BCH is divided into a plurality of blocksaccording to the type of information, and respectively broadcasted withindividual cycles in a unit referred to as SIB (System InformationBlock).

Furthermore, a variable-length (1 to 4 OFDM symbols) physical downlinkcontrol channel (PDCCH) is included at the top of each subframe. Thenumber of OFDM symbols used in a PDCCH is determined by a signalreferred to as PCFICH (Physical Control Format Indicator Channel)provided at the top of each subframe. Furthermore, although notillustrated, a reference signal (downlink reference signal, DL-RS)required for demodulation and measurement of reception quality isincluded in each resource block. The mobile station apparatus performsmeasurement of reception quality and channel compensation of the PDCCHusing the reference signal and, if there is data allocation in the PDCCHaddressed to the station itself, demodulates the PDSCH included in theOFDM symbol after the PDCCH to acquire data addressed to the stationitself.

In addition, the MBMS is defined which provides the same data to aplurality of mobile station apparatuses existing in a particular area inthe communication system. The MBMS includes a multicast service and abroadcast service, the former usually being a service provided to userswho have registered and subscribed to particular services, and thelatter being a service provided to all the users existing in theparticular area. As MBMS providing methods, there are MBSFN(Multicast/Broadcast over Single Frequency Network), SC-PTP (SingleCell-Point To Point), SC-PTM (Single Cell-Point To Multipoint), MC-PTM(Multi Cell-Point To Multipoint), or the like, as described in thenon-patent document 2.

In MBSFN, a plurality of adjacent base station apparatuses broadcaststhe same signal using the same subframe. It is advantageous thatoverhead is reduced when there are many mobile station apparatusesreceiving the service. SC-PTP is used if there are few mobile stationapparatuses receiving the MBMS or if it is desired to continue theservice when leaving the area broadcasted by MBSFN, and is transmittedto each mobile station apparatus as data addressed to the user using thePDSCH. It is effective if there are few mobile station apparatusesreceiving the service, or if there is a large difference in receptionquality among a plurality of mobile station apparatuses receiving theservice. PTM (point-to-multipoint) is used, for example, if a pluralityof mobile station apparatuses receiving the MBMS can form a group with asimilar degree of reception quality, and is transmitted using PDSCH orthe like, to the group, as data addressed to the group using an optimaltransmission parameter (modulation method, coding rate, etc.). PTMincludes SC-PTM in which only one cell performs transmission and MC-PTMin which transmission is performed from a plurality of cells.

In EUTRA, in release 9, the MBMS using MBSFN is provided. Furthermore,in release 10 (A-EUTRA), using PTM and SC-PTP is also under study. PTMhas been introduced in release 6 and the subsequent releases of thecurrent UMTS (Universal Mobile Telecommunications System). The overalloperation in Release 8 is described in the non-patent document 3, anddetails of the operation of RRC (Radio Resource Control) are describedin the non-patent document 4, respectively. In A-EUTRA also, MBMS isunder study based on this scheme.

As channels used in the UMTS when providing the MBMS via PTM, threechannels, i.e., an MBMS point-to-multipoint Traffic Channel (MTCH), anMBMS point-to-multipoint Control Channel (MCCH), and an MBMSpoint-to-multipoint Scheduling Channel (MSCH) have been defined asLogical Channels for the MBMS. Here, an MTCH is a channel fortransmitting data of the MBMS, that is, a data channel. Additionally, anMCCH is a channel including control information for providing the MBMS,that is, a control channel. Furthermore, an MSCH is a channel fortransmitting scheduling information of the MTCH, that is, a controlchannel.

Next, a transport channel is used by a Forward Access Channel (FACH) totransmit the three Logical Channels described above. Finally, a physicalchannel is used by the Secondary Common Control Physical Channel(S-CCPCH) to transmit the FACH described above.

Next, the layer 2 and the layer 3 will be mainly explained below.Messages of the MCCH include MBMS Access Information used for Countingdescribed below, MBMS Common PTM RB Information which is the commonsetting information among cells, MBMS Current Cell PTM RB Informationwhich is setting information for the cell of its own, MBMS NeighbouringCell PTM RB Information which is setting information for adjacent cells,MBMS General Information including general MBMS setting information orthe like, MBMS Modified Services Information including informationrelating to services which has been modified, and MBMS UnmodifiedServices Information including information relating to services whichhas not been modified.

A mobile station apparatus receives the above-mentioned MCCH messagesand performs settings thereof, and thereby can receive an MTCH whichactually transmits data or an MSCH which transmits schedulinginformation of the MTCH.

Next, Notification and Counting will be explained. The MBMS does notalways provide services, but provides services regularly or irregularly.In order to support such services, it is necessary to notify the mobilestation apparatus of the fact that the network starts providing aservice in which a user may be interested. This operation is referred toas Notification. The Notification includes the one checking whether ornot a service requested by the mobile station apparatus is beingprovided by the mobile station apparatus directly checking the MBMSModified Services Information and MBMS Unmodified Services Informationdefined in the MCCH, and the one determining whether or not it isnecessary to check the above-mentioned MBMS Modified ServicesInformation by checking the MBMS Indicator Channel (MICH), andperforming the checking only when necessary.

Furthermore, the network can determine both the necessity of providingany of the services to be provided as the MBMS and the method ofproviding the service by performing the Counting described below.

First, the network causes a parameter called a Probability factor to beincluded in the MBMS ACCESS INFORMATION which is periodicallytransmitted as information for performing the Counting for a service tobe provided from now on to the mobile station apparatus. The Probabilityfactor may either have a value for a mobile station apparatus in an idlestate and a value for a mobile station apparatus in a connected stateindividually set, or use a same value for both states. Furthermore, themobile station apparatus is prompted to acquire the MBMS ACCESSINFORMATION by causing a signal (Acquire Counting Info) which prompts toacquire Counting information to be included in the MBMS ModifiedServices Information. In the following explanation, message transmissionfor performing the above-mentioned Counting is generally referred as aCounting signal.

The above-mentioned Probability factor is a parameter for preventingline congestion caused by response from all the mobile stationapparatuses requesting a particular service. Specifically, among themobile station apparatuses requesting a particular service, only themobile station apparatus with the generated random number not exceedingthe Probability factor responds. The network can know, by recognizing,among the mobile station apparatuses requesting a particular service,the mobile station apparatus which responded based on the Probabilityfactor acquired from the MBMS ACCESS INFORMATION, that it is necessaryto provide the service to that cell. If there is no response from themobile station apparatuses, the network can modify the Probabilityfactor to a larger value so that a larger number of mobile stationapparatuses can respond.

The network next determines how to provide the services. For example,since Multicast transmits the same information to a plurality of mobilestation apparatuses, it is necessary to perform transmission with a highelectric power, considering mobile station apparatuses existing at thecell edge (cell end). However, if there are few mobile stationapparatuses requesting a particular service, there may be a case that itis better to transmit the same information respectively to individualmobile station apparatuses. For example, if there are four or moremobile station apparatuses, the network provides a service via PTM usingthe FACH which has been mapped on the S-CCPCH and, if there are lessthan four mobile station apparatuses, provides a service individuallyvia PTP using a DCH (Dedicated Channel) which has been mapped on aDL-DPDCH (Down Link-Dedicated Physical Data Channel). In other words,the network confirms the number of mobile station apparatuses requestinga service to be provided by Counting, and switches MBMS providingmethods in the UMTS.

In addition, if there is a mobile station apparatus in a poor receptionstate when providing the MBMS via PTM, the patent document 1 proposesindividually providing a service via SC-PTP to the mobile stationapparatus in a poor reception state, while continuing the service viaPTM. Furthermore, if the number of mobile station apparatuses receivinga service via SC-PTP exceeds a certain number, it is proposed to reducethe number of mobile stations requiring the service via SC-PTP byincreasing the transmission power of PTM. In other words, an approach ofsetting two providing methods (PTM and SC-PTP) as appropriate, based onthe reception state of PTM in the receiving mobile station apparatus isproposed.

-   Patent Document 1: Japanese Patent Laid-Open No. 2006-135956-   Non-Patent Document 1: 3GPP TR36.913, Requirements for Further    Advancements for    E-UTRA.V8.0.0http://www.3gpp.org/ftp/Specs/html-info/36913.htm-   Non-Patent Document 2: Alcatel-Lucent, R2-080983, 3GPP TSG-RAN2    Meeting #61, Sorrento, Italy, Feb. 11-15, 2008-   Non-Patent Document 3: 3GPP TS25.346,    V8.3.0http://www.3gpp.org/ftp/Specs/html-info/25346.htm-   Non-Patent Document 4: 3GPP TS25.331,    V8.7.0http://www.3gpp.org/ftp/Specs/html-info/25331.htm

DISCLOSURE OF THE INVENTION

FIG. 13 illustrates the overall configuration of a wirelesscommunication system. As described above, in the UMTS, the MBMS canswitch the providing methods according to the number of mobile stationapparatuses requesting a service. However, although provision of serviceis performed via PTM based on the number of mobile station apparatuses 1when there are mobile station apparatuses 1A, 1B and 1C in the vicinityof the cell center, and a mobile station apparatus 1D at the cell edgeas shown in FIG. 13 (hereinafter mobile station apparatuses (1A to 1D)are expressed as mobile station apparatuses 1), it is necessary toperform transmission with a modulation/encoding scheme robust to noiseand a high electric power so that even the mobile station apparatus 1Dat the cell edge can receive, which may result in wasted radio resourcesand electric power.

Additionally, in the patent document 1, the number and arrangement ofthe mobile station apparatuses 1 requesting reception of an MBMS in aservice cell are grasped based on the information of the reception stateof the MBMS, which is first transmitted via PTM from a base stationapparatus 3 to the mobile station apparatuses 1 in the service cellrequesting reception of the MBMS and then transmitted from the mobilestation apparatuses 1 to the base station apparatus 3.

However, the approach uses the MBMS transmitted via PTM using a largeamount of communication resources only for grasping the number andarrangement of the mobile station apparatuses 1 in the service cellrequesting reception of the MBMS, resulting in problems such asdegradation of usage efficiency of communication resources or increaseof processes in the mobile station apparatuses 1.

Considering the above problems, it is an object of the present inventionto provide a wireless communication system, a base station apparatus, amobile station apparatus, and a communication method which avoidsproblems such as degradation of usage efficiency of communicationresources or increase of processes in the mobile station apparatus bymaking it easier to grasp the number and arrangement of mobile stationsin a service cell requesting reception of an MBMS.

(1) In order to achieve the above object, the present invention hastaken the following measures. That is, the wireless communication systemof the present invention is a wireless communication system including abase station apparatus and mobile station apparatuses to provide an MBMS(Multimedia Broadcast Multicast Service), in which the base stationapparatus transmits a message for aggregating the number of mobilestation apparatuses requesting an MBMS to a mobile station apparatusbeing served; and among the mobile station apparatuses, the mobilestation apparatus requesting an MBMS adds intra-cell locationinformation of the mobile station itself to a response message to themessage and transmits the response message added with the intra-celllocation information to the base station apparatus.

As thus described, since intra-cell location information of a mobilestation apparatus requesting an MBMS is added to a response message fora message and the response message having the intra-cell locationinformation added thereto is transmitted to the base station apparatus,it becomes possible to provide an appropriate MBMS based on theintra-cell location of the mobile station apparatus, enabling effectiveutilization of radio resources thereby. In addition, since the processrequired in the mobile station apparatus only adds to the Countingresponse a signal based on reception power of the downlink referencesignal which has always been being measured and uses it to select aproviding method in the Notification, increase of power consumption canbe suppressed without requiring a complicated process. Furthermore, italso becomes possible to provide optimal transmission parameters evenwhen many mobile station apparatuses requesting the service are in thevicinity of the cell center.

(2) In addition, the wireless communication system of the presentinvention is a wireless communication system including a base stationapparatus and mobile station apparatuses to provide an MBMS (MultimediaBroadcast Multicast Service), in which the base station apparatus addsthreshold information of intra-cell location of the mobile stationapparatus to a message for aggregating the number of mobile stationapparatuses requesting an MBMS and transmits the message added with thethreshold information to the mobile station apparatus being served, andamong the mobile station apparatuses, the mobile station apparatusrequesting an MBMS determines whether or not to respond to the messagebased on the threshold information of intra-cell location and theintra-cell location of its own.

As thus described, since a mobile station apparatus requesting an MBMSdetermines whether or not to respond to a message based on the thresholdinformation of intra-cell location and the intra-cell location, itbecomes possible to acquire NumE and NumC for use in determining theMBMS providing method while reducing the amount of information requiredin a Counting response. In addition, it becomes possible to classifytarget mobile station apparatuses to be responded, whereby linecongestion at the time of responding can be reduced even if theProbability factor value is set high. In addition, it becomes possibleto provide an appropriate MBMS based on the intra-cell location of themobile station apparatus, enabling effective utilization of radioresources thereby. In addition, since the process required in the mobilestation apparatus only adds to the Counting response a signal based onreception power of the downlink reference signal which has always beenbeing measured and uses it to select a providing method in theNotification, increase of power consumption can be suppressed withoutrequiring a complicated process. Furthermore, it also becomes possibleto provide optimal transmission parameters even if there are many mobilestation apparatuses requesting service in the vicinity of the cellcenter.

(3) Additionally, in the wireless communication system of the presentinvention, the base station apparatus receives the response message fromthe mobile station apparatus, aggregates the number of mobile stationapparatuses requesting an MBMS for each intra-cell location, andprovides an MBMS to the mobile station apparatus based on an MBMSproviding method determined for the each intra-cell location.

As thus described, since the base station apparatus aggregates thenumber of mobile station apparatuses requesting an MBMS for eachintra-cell location and provides the MBMS to the mobile stationapparatus based on an MBMS providing method determined for eachintra-cell location, enabling effective utilization of radio resourcesthereby. In addition, it also becomes possible to provide optimaltransmission parameters even if there are many mobile stationapparatuses requesting service in the vicinity of the cell center.

(4) Additionally, in the wireless communication system of the presentinvention, the base station apparatus transmits a message for notifyingthe MBMS providing method to a mobile station apparatus requesting anMBMS and, if a plurality of MBMS providing methods are included in themessage for notifying the MBMS providing method, the mobile stationapparatus selects an MBMS providing method based on intra-cell locationinformation of its own.

As thus described, since the mobile station apparatus selects an MBMSproviding method based on intra-cell information of its own, if aplurality of MBMS providing methods is included in the message fornotifying an MBMS providing method, the base station apparatus needs notperform transmission to a mobile station apparatus in the vicinity ofthe cell center via PTM similarly to a mobile station apparatus at thecell edge if there are mobile station apparatuses in the vicinity of thecell center and at the cell edge, suppressing waste of radio resourcesand electric power thereby. In addition, a mobile station apparatusreceiving a service via SC-PTP needs not measure reception quality ofPTM in order to switch to reception via PTM, and whereby it becomespossible to prevent increase of processes in the mobile stationapparatus.

(5) Additionally, in the wireless communication system of the presentinvention, the MBMS providing method is one of MBSFN(Multicast/Broadcast over Single Frequency Network), SC-PTP (SingleCell-Point To Point), SC-PTM (Single Cell-Point To Multipoint), andMC-PTM (Multi Cell-Point To Multipoint).

As thus described, since the MBMS providing method is one of MBSFN(Multicast/Broadcast over Single Frequency Network), SC-PTP (SingleCell-Point To Point), SC-PTM (Single Cell-Point To Multipoint), andMC-PTM (Multi Cell-Point To Multipoint), it becomes possible to providean optimal MBMS according to the number or location of mobile stationapparatuses, difference of reception quality, or the like.

(6) Additionally, in the wireless communication system of the presentinvention, the intra-cell location information is two-value informationindicating the vicinity of the cell center and the vicinity of the celledge.

As thus described, the intra-cell location information is two-valueinformation indicating the vicinity of the cell center or the vicinityof the cell edge, for example. The intra-cell location information maytherefore be one-bit data with the vicinity of the cell center set toone and the vicinity of the cell edge set to zero, eliminating thenecessity of a complicated process thereby.

(7) Additionally, in the wireless communication system of the presentinvention, the intra-cell location information is either RSRP (ReferenceSignal Received Power) or a path-loss value.

As thus described, since the intra-cell location information is eitherRSRP or a path loss value, the mobile station apparatus can suppressincrease of power consumption without requiring a complicated process.

(8) In addition, the base station apparatus of the present invention isa base station apparatus applied to a wireless communication systemincluding a base station apparatus and mobile station apparatuses toprovide an MBMS (Multimedia Broadcast Multicast Service), in which thebase station apparatus transmits a message for aggregating the number ofmobile station apparatuses requesting an MBMS to a mobile stationapparatuse being served, and receives a response message correspondingto the message from the mobile station apparatus, aggregates the numberof mobile station apparatuses requesting an MBMS for each intra-celllocation of the mobile station apparatus, and provides an MBMS to themobile station apparatus based on an MBMS providing method determinedfor the each intra-cell location.

As thus described, since the base station apparatus provides an MBMS toa mobile station apparatus based on an MBMS providing method determinedfor each intra-cell location of a mobile station apparatus, it becomespossible to provide an appropriate MBMS based on the intra-cell locationof a mobile station apparatus, enabling effective utilization of radioresources thereby. In addition, since the process required in the mobilestation apparatus only adds to the Counting response a signal based onreception power of the downlink reference signal which has always beenbeing measured and uses it to select a providing method in theNotification, increase of power consumption can be suppressed withoutrequiring a complicated process. Furthermore, it also becomes possibleto provide optimal transmission parameters even if there are many mobilestation apparatuses requesting service in the vicinity of the cellcenter.

(9) In addition, the base station apparatus of the present inventioncomprises a transmission signal processing unit which generates atransmission signal including a message for notifying at least one MBMSproviding method associated with location information of a mobilestation apparatus in a cell, and a transmitting unit which transmits thegenerated transmission signal to the mobile station apparatus.

As thus described, since the base station apparatus generates atransmission signal including a message for notifying at least one MBMSproviding method associated with intra-cell location information of amobile station apparatus, it becomes possible to provide an appropriateMBMS based on the intra-cell location of the mobile station apparatus,enabling effective utilization of radio resources thereby.

(10) In addition, the mobile station apparatus of the present inventionis a mobile station apparatus applied to a wireless communication systemincluding a base station apparatus and mobile station apparatuses toprovide an MBMS (Multimedia Broadcast Multicast Service), in which themobile station apparatus receives from the base station apparatus amessage for aggregating the number of mobile station apparatusesrequesting an MBMS and, when requesting an MBMS, adds intra-celllocation information of its own to a response message to the message totransmit the response message added with the intra-cell locationinformation to the base station apparatus.

As thus described, since the mobile station apparatus adds intra-cellinformation of its own to a response message to the message, it becomespossible for the base station apparatus to provide an appropriate MBMSbased on the intra-cell location of the mobile station when an MBMS isrequested, enabling effective utilization of radio resources thereby.

(11) In addition, the mobile station apparatus of the present inventioncomprises a Counting response signal generating unit which, uponreceiving a message for aggregating the number of mobile stationapparatuses requesting an MBMS from the base station apparatus, addsintra-cell information of its own to a response message corresponding tothe message.

As thus described, upon receiving a message for aggregating the numberof mobile station apparatuses requesting an MBMS from the base stationapparatus, the mobile station apparatus adds intra-cell information ofits own to a response message corresponding to the message, and wherebyit becomes possible for the base station apparatus to provide anappropriate MBMS based on the intra-cell location of the mobile station,enabling effective utilization of radio resources thereby.

(12) In addition, the mobile station apparatus of the present inventioncomprises a Counting response signal generating unit which, uponreceiving a message for aggregating the number of mobile stationapparatuses requesting an MBMS from the base station apparatus,determines whether or not to transmit a response message correspondingto the message based on the intra-cell information of its own.

As thus described, since the mobile station apparatus determines whetheror not to transmit a response message corresponding to a message basedon intra-cell location information of its own, upon receiving a messagefor aggregating the number of mobile station apparatuses requesting anMBMS from a base station apparatus, it becomes possible for the basestation apparatus to acquire NumE and NumC for use in determining theMBMS providing method while reducing the amount of information requiredby the mobile station apparatus in the Counting response.

(13) In addition, upon receiving a transmission signal including amessage for notifying at least one MBMS providing method associated withintra-cell location information of a mobile station apparatus from thebase station apparatus, the mobile station apparatus of the presentinvention selects the MBMS providing method based on the intra-cellinformation of its own.

As thus described, since the mobile station apparatus selects an MBMSproviding method based on the intra-cell information of its own, uponreceiving a transmission signal including a message for notifying atleast one MBMS providing method associated with intra-cell locationinformation of a mobile station apparatus from a base station apparatus,the base station apparatus needs not perform transmission to a mobilestation apparatus in the vicinity of the cell center via PTM similarlyto a mobile station apparatus at the cell edge, suppressing waste ofradio resources and electric power thereby. In addition, a mobilestation apparatus receiving service provision via SC-PTP needs notmeasure reception quality of PTM in order to switch to reception viaPTM, and whereby it becomes possible to prevent increase of processes inthe mobile station apparatus.

(14) In addition, the communication method of the present invention is acommunication method of a wireless communication system including a basestation apparatus and mobile station apparatuses to provide an MBMS(Multimedia Broadcast Multicast Service), the method comprising at leastthe steps of: in the base station apparatus, transmitting a message foraggregating the number of mobile station apparatuses requesting an MBMSto a mobile station apparatus being served; and in a mobile stationapparatus requesting an MBMS among the mobile station apparatuses,adding intra-cell location information of the mobile station itself to aresponse message to the message; and transmitting the response messageadded with the intra-cell location information to the base stationapparatus.

As thus described, since a mobile station apparatus requesting an MBMSadds intra-cell information of its own to a response message to themessage, it becomes possible to provide an appropriate MBMS based on theintra-cell location of the mobile station apparatus, enabling effectiveutilization of radio resources thereby.

(15) In addition, the communication method of the present invention is acommunication method of a wireless communication system including a basestation apparatus and mobile station apparatuses to provide an MBMS(Multimedia Broadcast Multicast Service), the method comprising at leastthe steps of: in the base station apparatus, adding thresholdinformation of intra-cell location of a mobile station apparatus to amessage for aggregating the number of mobile station apparatusesrequesting an MBMS; and transmitting the message added with thethreshold information to a mobile station apparatus being served; and ina mobile station apparatus requesting an MBMS among the mobile stationapparatuses, determining whether or not to respond to the message basedon the threshold information of intra-cell location and intra-celllocation of the mobile station itself.

As thus described, since the mobile station apparatus requesting an MBMSdetermines whether or not to respond to a message based on the thresholdinformation of the intra-cell location and its own intra-cell location,it becomes possible for the base station apparatus to acquire NumE andNumC for use in determining the MBMS providing method while reducing theamount of information required by the mobile station apparatus in theCounting response.

According to the present invention, since a mobile station apparatusrequesting an MBMS adds intra-cell information of its own to a responsemessage to a message and transmits the response message added with theintra-cell location information to a base station apparatus, it becomespossible to provide an appropriate MBMS based on the intra-cell locationof the mobile station apparatus, enabling effective utilization of radioresources thereby. In addition, since the process required in the mobilestation apparatus only adds to the Counting response a signal based onreception power of the downlink reference signal which has always beenbeing measured and uses it to select a providing method in theNotification, increase of power consumption can be suppressed withoutrequiring a complicated process. Furthermore, it also becomes possibleto provide optimal transmission parameters even if there are many mobilestation apparatuses requesting service in the vicinity of the cellcenter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an exemplary receiving device ofthe UE1 according to the embodiment of the present invention;

FIG. 2 is a block diagram illustrating an exemplary transmitting deviceof the UE1 according to the embodiment of the present invention;

FIG. 3 is a block diagram illustrating an exemplary receiving device ofan eNB3 according to the embodiment of the present invention;

FIG. 4 is a block diagram illustrating an exemplary transmitting deviceof an eNB3 according to the embodiment of the present invention;

FIG. 5 is a schematic block diagram illustrating the overall user planearchitecture of providing an MBMS including the UE1 and the eNB3according to the embodiment of the present invention;

FIG. 6 is a sequence chart of providing an MBMS based on the user planearchitecture according to the embodiment of the present invention;

FIG. 7 is a flow chart illustrating an exemplary procedure of a Countingresponse process in the UE1 according to a first embodiment of thepresent invention;

FIG. 8 is a flow chart which an exemplary procedure of an MBMS providingmethod determination process in an NW according to the first embodimentof the present invention;

FIG. 9 is a flow chart illustrating an exemplary procedure of areception setting process in the UE1 according to the first embodimentof the present invention;

FIG. 10 is a flow chart illustrating an exemplary procedure of theCounting response process in the UE1 according to a second embodiment ofthe present invention;

FIG. 11 is a flow chart illustrating an exemplary procedure of theCounting response process in the UE1 according to a third embodiment ofthe present invention;

FIG. 12 illustrates an exemplary configuration of a downlink radio framein EUTRA; and

FIG. 13 illustrates the overall configuration of a wirelesscommunication system.

BEST MODES FOR CARRYING OUT THE INVENTION First Embodiment

A first embodiment of the present invention will be explained below,referring to FIGS. 1 to 9.

FIG. 1 is a block diagram illustrating an exemplary receiving device ofa mobile station apparatus (expressed as UE in the following) 1according to an embodiment of the present invention. The receivingdevice 100 includes a receiving unit 101, a reception signal processingunit 102, a measurement information holding unit 103, a Countingresponse signal generating unit 104, and an antenna 105. A receptionsignal (transmission signal from the base station apparatus (expressedas eNB in the following) 3) is received in the receiving unit 101 viathe antenna 105.

In the receiving unit 101, the reception signal is demodulated based onreception control information indicating the channel schedule. Thereception control information includes information related todemodulation such as reception timing with regard to each channel,multiplexing method, resource allocation information, or scramblerelease codes. The receiving unit 101 demodulates and decodes thereception signal for each channel according to the reception controlinformation, and outputs it to the reception signal processing unit 102.In addition, the receiving unit 101 outputs a physical cell ID detectedfrom a synchronization channel included in the reception signal,reception quality of the downlink reference signal, and area informationor base station transmission power information acquired from thebroadcast information to the measurement information holding unit 103 asmeasurement information. The measurement information holding unit 103outputs the measurement information held therein to an higher layer (notshown) or the Counting response signal generating unit 104.

The reception signal processing unit 102 processes the input signal fromthe receiving unit 101 for each channel and, if a Counting signal of theMBMS is included, outputs the signal to the Counting response signalgenerating unit 104. Explanation of traffic data or downlink controldata of other users which are output to individual process blocks asother information will be omitted since they are irrelevant to thepresent invention.

Upon detecting a Counting signal, the Counting response signalgenerating unit 104 determines whether or not to generate a Countingresponse signal based on the Probability factor, the service requestsignal and the base station transmission power information acquired fromthe higher layer, and the measurement information acquired from themeasurement information holding unit 103 and, if so, generates theCounting response signal and outputs it to a transmitting device 200described below.

FIG. 2 is a block diagram illustrating an exemplary transmission deviceof the transmitting device of the UE1 according to the embodiment of thepresent invention. The transmitting device 200 includes a transmissionsignal processing unit 201, a transmitting unit 202, and an antenna 203.A Counting response signal is input to the transmission signalprocessing unit 201 according to an instruction from the higher layer atan appropriate timing. The transmission signal processing unit 201performs appropriate scheduling for the Counting response signal andother transmission signals. Other transmission signals refer to uplinkuser traffic data and uplink control data, uplink reference signals, orthe like. The signal output from the transmission signal processing unit201 based on scheduling is output from the transmitting unit 202 via theantenna 203 as a transmission signal according to transmission controlinformation. The transmission control information includes informationrelated to transmission timing with regard to each channel, multiplexingmethod, resource allocation information, and modulation. In FIGS. 1 and2, since other components of the UE1 are irrelevant to the presentembodiment, explanation thereof will be omitted.

FIG. 3 is a block diagram illustrating an exemplary receiving device ofthe eNB3 according to the embodiment of the present invention. Thereceiving device 300 includes a receiving unit 301, a reception signalprocessing unit 302, a Counting response signal aggregating unit 303,and an antenna 304. The reception signal (transmission signal from theUE1) is received by the receiving unit 301 via the antenna 304. Thereceiving unit 301 demodulates the reception signal based on thereception control information indicating the channel schedule. Thereception control information includes information related to receptiontiming with regard to each channel for each UE1, multiplexing method,resource allocation information and demodulation. The receiving unit 301demodulates and decodes the reception signal for each channel accordingto the reception control information, and outputs it to the receptionsignal processing unit 302.

The reception signal processing unit 302 divides the input signal foreach UE1 and processes it for each channel as appropriate. If the inputsignal is a Counting response signal, the Counting response signal isoutput to the Counting response signal aggregating unit 303. Signalsother than the Counting response signal processed in the receptionsignal processing unit 302 such as user traffic data, uplink controldata, and other control messages, for example, are input to individualprocess blocks as other information, however, explanation thereof willbe omitted since they are irrelevant to the present invention. TheCounting response signal aggregating unit 303 aggregates the Countingresponse signal for each user and notifies the count result to thehigher layer.

FIG. 4 is a block diagram illustrating an exemplary transmitting deviceof the eNB3 according to the embodiment of the present invention. Thetransmitting device 400 includes a transmission signal processing unit401, a transmitting unit 402, and an antenna 403. An MBMS providingmethod setting signal, MBMS data and other transmission signals areinput to the transmission signal processing unit 401 from the higherlayer. The transmission signal processing unit 401 generates, based onthe MBMS providing method setting signal, a transmission signal of theMBMS data using any of the providing methods of MBSFN, PTM, and SC-PTP,or a combination of these methods, and performs scheduling with othertransmission signals included therein. Other transmission signals referto downlink user traffic data, downlink control data, or downlinkreference signal of each UE1. The data output from the transmissionsignal processing unit 401 based on the scheduling is output from thetransmitting unit 402 via the antenna 403 as a transmission signalaccording to a transmission control information. The transmissioncontrol information includes information related to transmission timingwith regard to each channel, multiplexing method, resource allocationinformation, and modulation. In FIGS. 3 and 4, other components of theeNB3 are omitted since they are irrelevant to the present invention.

FIG. 5 is a schematic block diagram illustrating the overall user planearchitecture of providing an MBMS including the UE1 and the eNB3according to the embodiment of the present invention. In FIG. 5, the UE1is a mobile station apparatus, the eNB3 is a base station apparatus, theeBM-SC (evolved Broadcast/Multicast-Service Center) 501 is the source ofthe MBMS traffic, and the E-MBMSGW (E-MBMS Gateway) 502 is a logicentity which distributes the traffic to various eNB3s in an MBMSprovision area. The E-MBMS GW 502 may be implemented on a device onanother network. In FIG. 5, an MBMS packet generated in the eBM-SC 501is sent to each eNB3 through the E-MBMSGW 502, and each eNB3 holds theMBMS packet until a timing (radio frame) has been reached to transmitthe MBMS packet according to a SYNC protocol sent from the E-MBMSGW 502,and transmits it to the UE1 according to the transmission timing withMBSFN or MC-PTM.

Additionally, in the control plane, although not shown, an MCE (MBMSCoordination Entity) which controls all the eNB3s in a provision areaexists as an entity so that the same resource block is allocated to anarbitrary service in an area where the MBMS is provided with MBSFN orMC-PTM, and control is performed so that the transmission timing in theradio frame coincides with the MBMS provision area. Since the MCE is alogical entity, the MCE may be implemented on the eNB3, or on anotherdevice on the network. The MCE is controlled by an MME (MobilityManagement Entity), and the control signal of an MBMS session from theE-MBM SGW 502 is sent to the MCE via the MME.

In addition, when an MBMS packet is transmitted via SC-PTP or SC-PTM,the E-MBM SGW 502 may generate a packet for each UE1 and transmit toeach UE1 as a normal packet, or the eNB3 may perform scheduling of aradio resource and transmit, to the UE1, the MBMS packet as a packetaddressed to the UE1. The MBMS is provided to a user according to theabove-mentioned architecture.

FIG. 6 is a sequence chart of providing an MBMS based on the user planearchitecture according to an embodiment of the present invention. InFIG. 6, the UE1 is a mobile station apparatus and the NW 601 is anetwork including a plurality of (MCE-implementing) eNB3s, MMEs, S-GWs(Serving Gateway), and P-GWs (PDN Gateway). The -MBM SGW 502 may existin the above-mentioned NW 601 and, if it belongs to another network, theMBMS is provided to the UE1 through the MME and the P-GW of the NW 601.

First, an MBMS provider uses an SMS (Short Message Service) or an MMS(Multimedia Message Service) to perform Service announcement to the UE1(step S101). The UE1 may be required to perform Subscriptionpreliminarily in order to receive the Service announcement from the MBMSprovider. The Service announcement includes information such as servicecontent or provision time of an MBMS including a plurality of sessions,containing a schedule for several hours or several days. The UE1 whichreceived the Service announcement performs Joining (step S102)indicating that it will receive one or more MBMS Bearer services whenrequesting a service. As the Joining, The UE1 transmits to the NW 601 aJoin message having included therein at least an IP multicast addresswhich can identify the MBMS Bearer service to be received. The UE1 mayperform the Joining before starting a Session described below, orperform it during the Session.

Next, the NW 601 performs MBMS session start when transmission of theMBMS data has become possible to establish an MBMS Bearer for receivingMBMS data of a session started for the UE1 (step S103). Next, the NW 601transmits a Counting signal to the UE1 if it required to performCounting (step S104), and receives a Counting Response from the UE1(step S105). In addition, it changes the Probability Factor and performsthe Counting process again whenever necessary for a case such that thereis no Counting response (steps S106 and S107).

Next, the NW 601 determines the MBMS providing method (step S108), andperforms Notification to the UE1. In the Notification, Bearer resourcesfor MBMS transmission are allocated to the UE1 (step S109). The NW 601can determine allocation information of Bearer resources for MBMStransmission to be notified in the Notification based on the Countingresponse. The UE1 which received the Notification starts receiving oneor more MBMS Bearer services in order to receive the MBMS data.Subsequently, the NW 601 transmits the MBMS data using the resourcesallocated to the UE1 (step S110).

If the NW 601 determines, after MBMS data transmission in one sessionhas finished, that there is sufficient time to release the MBMS Beareruntil the next session, the NW 601 transmits SessionStop to the UE1 andreleases the MBMS Bearer resources of the session of the UE1 (stepS111). In addition, the UE1 requesting to stop reception of the MBMSperforms Leaving to the NW 601 (step S112). As the Leaving, the UE1transmits to the NW 601 a Leave message having included therein at leastan IP multicast address which can identify the MBMS Bearer service ofwhich it desires to stop reception. An MBMS is provided to the UE1 bythe above sequence.

Next, Counting and determination of the providing method in the aboveprocedure of the present embodiment will be described in detail. In thepresent embodiment, location information of the UE1 in the cell is newlyadded to the conventional Counting response.

Positional information in a cell is information indicating whether atleast the UE1 is in the vicinity of the cell center or at the cell edge.Whether the UE1 is in the vicinity of the cell center or in the vicinityof the cell edge may be determined by comparing, for example, thedistance between two points calculated from the location informationcalculated by GPS and the location information of the eNB3 included inthe broadcast information with a predetermined threshold value or,without being limited to physical location information, may bedetermined by comparing, with a predetermined threshold, the path lossvalue, the RSRP itself, or reception quality (RSRQ) of the referencesignal calculated from the reception power (RSRP) of a downlinkreference signal received by the UE1 and the transmission powerinformation (base station transmission power information) included inthe broadcast information. In the present embodiment, a case of usingthe path loss value will be explained. Any method other than thatdisclosed in the present invention may be used provided that locationinformation in the cell can be acquired, and it is also possible toacquire the location information in the cell using, for example, theLocation Service (LCS) in a future mobile communication system.

FIG. 7 is a flow chart illustrating an exemplary procedure of theCounting response process in the UE1 according to the first embodimentof the present invention. Upon receiving a Counting signal from the NW601 (typically the eNB3), the UE1 determines whether or not a service isrequested in the Counting response signal generating unit 104 shown inFIG. 1, based on the service request signal input from the higher layer(step S201). When no service is being requested, the UE1 terminates theflow. If a service is being requested, the UE1 determines whether or notit will transmit a Counting response signal based on the Probabilityfactor included in MBMS ACCESS INFORMATION (step S202). The UE1terminates the flow is it will not perform transmission.

In the case of transmitting a Counting response signal, the UE1calculates the path loss value from the base station transmission powerinformation input from the higher layer and the measurement result ofreception power of the downlink reference signal held in the measurementinformation holding unit 103, and compares the path loss value with apredetermined threshold value (step S203). Here, the predeterminedthreshold value may be preliminarily included in the broadcastinformation from the eNB3, or may be included in the Counting signal. Inaddition, the base station transmission power information ispreliminarily notified from the eNB3 by the broadcast information. If,as a result of comparison between the calculated path loss value and thepredetermined threshold, the path loss value is less than the threshold,a code indicating the vicinity of the cell center is set as theintra-cell location information (step S204). If the path loss value isnot less than the threshold, a code indicating the vicinity of the celledge is set as the intra-cell location information (step S205).

Here, the code of the intra-cell location information may be any codeprovided that it is preliminarily determined by the eNB3 and the UE1.For example, it may be one-bit data with the vicinity of the cell centerset to one and the vicinity of the cell edge set to zero, or may beexpressed by setting two types of random access preambles for use intransmitting a Counting response signal and selecting one of thepreambles to be used. Alternatively, only the UE1 in the vicinity of thecell edge may add the data indicating the vicinity of the cell edge tothe Counting response signal and transmit it. Next, the code which hasbeen set at step S204 or S205 is input to the transmission signalprocessing unit of the transmitting device of FIG. 2 in a mannerincluded in the Counting response signal (step S206). The foregoing isthe procedure of the Counting response process in the UE1. Next, adetermination procedure of an MBMS providing method in the NW 601receiving the Counting response will be explained.

FIG. 8 is a flowchart illustrating an exemplary procedure of the MBMSproviding method determination process in the NW 601 according to thefirst embodiment of the present invention. The eNB3 in the NW 601 firsttransmits the Counting signal to the UE1 under control thereof (stepS301). The eNB3 collects, in the Counting response signal aggregatingunit 303, the Counting response signals transmitted from the UE1 andcounts, as the intra-cell location information, the number of UEs (NumC)that has returned the vicinity of the cell center and the number of UEs(NumE) that has returned the vicinity of the cell edge (step S302).Next, it determines whether or not Counting is required again (stepS303).

If Counting is required, the eNB3 updates the value of the Probabilityfactor (step S304), returns to step S301 and performs the Countingagain. Here, one or both of the NumC and NumE counted at theabove-mentioned step S302 being 0 can be given as a case where Countingis required again. If Counting again is unnecessary, information of theNumC and NumE aggregated in the eNB3 is notified to the E-MBM SGW 502(step S305).

Steps S306 to S310 are processes in the E-MBM SGW 502, in which theE-MBM SGW 502 aggregates NumC and NumE notified from each eNB3 tocompare with a predetermined threshold, and sets, based on the result ofcomparison, a method of providing an MBMS to the UE1 in the vicinity ofthe cell center and a method of providing an MBMS to the UE1 in thevicinity of the cell edge. As an exemplary setting, by transmitting withMBSFN or MC-PTM instead of SC-PTP or SC-PTM if NumE≧threshold value Bholds (step S306), i.e., if the number of UE1s requesting a service inthe vicinity of the cell edge is not less than a certain value, the UE1in the vicinity of the cell center can also receive the service whilemaintaining the reception quality at the cell edge (step S310).

In addition, if NumC<threshold value A and NumE<threshold value B hold(steps S306 and S307), i.e., if the number of UE1s requesting service ina cell is less than a certain value, efficiency of resources can beexpected to increase by setting optimal transmission parameters(modulation method and coding rate) for each UE1 or for a group of UEsin the vicinity of the cell center and a group of UEs in the vicinity ofthe cell edge and transmitting via SC-PTP or SC-PTM in order to preventdrop of resource usage efficiency due to transmission with MBSFN orMC-PTM (step S309).

In addition, if NumC≧threshold value A and NumE<threshold value B hold(steps S306 and S307), i.e., if there are many UE1s requesting a servicein the vicinity of the cell center, efficiency of resource can beexpected to increase by transmitting to a group of UEs in the vicinityof the cell center with SC-PTM having a high transmission rate andtransmitting to the UE1 or a group of UEs in the vicinity of the celledge via SC-PTP or SC-PTM having a low transmission rate in order toprevent drop of resource usage efficiency due to transmission with MBSFNor MC-PTM having set therein transmission parameters to allow receptionin the vicinity of the cell edge. Power saving of the UE1 can also beexpected due to shortened reception processing time of the UE1 in thevicinity of the cell center by appropriately setting transmissionparameters (step S308).

Next, the Notification to the UE1 from the eNB3 is performed based onthe MBMS providing method which has been set at steps S306 to S310 (stepS311). Two types of providing methods notified in the Notification areincluded if the methods differ for the UE1 in the vicinity of the cellcenter and for the UE1 in the vicinity of the cell edge. In other words,although either a PTM information acquisition request signal(acquirePTM-RBInfo) or a PTP connection instruction signal(requestPTPRB) is notified from the eNB3 to the UE1 conventionally, thepresent embodiment has introduced a technique of sending theabove-mentioned signals separately to the UE1 in the vicinity of thecell center and the UE1 in the vicinity of the cell edge, or a techniqueof expanding the types of the above-mentioned signals and using a singlesignal which indicates instructions to both the UE1 in the vicinity ofthe cell center and the UE1 in the vicinity of the cell edge (e.g.,acquirePTM-RBInfoForCellCenter-requestPTPRBForCellEdge, etc.).

The MBMS providing method is determined by the above-mentioned flow, andBearer resources for transmitting the MBMS is notified to the UE1 by theNotification. If a plurality of providing methods described above isincluded in the Notification, the UE1 selects a providing method basedon intra-cell information of its own and performs a reception settingaccording to the selected providing method.

FIG. 9 is a flow chart illustrating an exemplary procedure of thereception setting process in the UE1 according to the first embodimentof the present invention. In FIG. 9, the UE1 requesting a service firstacquires a message including the providing method in the Notificationfrom the eNB3 (step S401). The UE1 then determines whether or not aplurality of providing methods is included in the message (step S402).If a single providing method is included, the UE1 acquires the providingmethod (step S403). If a plurality of providing methods is included, theUE1 determines whether or not the station itself is in the vicinity ofthe cell center (step S404). The determination method is the same asthat in the processing for the Counting response. If the station itselfis in the vicinity of the cell center, the UE1 acquires the providingmethod for the vicinity of the cell center (step S405). If the stationitself is in the vicinity of the cell edge, the UE1 acquires theproviding method for the vicinity of the cell edge (step S406).

Next, it is determined whether or not the providing method acquired inany of steps S406 to S404 is a PTM information acquisition instruction(step S407). If the providing method is a PTM information acquisitioninstruction, information required for receiving a service is acquiredfrom each PTM RB INFORMATION included in the MCCH (step S408). If theproviding method is not a PTM information acquisition instruction, it isdetermined whether or not the providing method is an MBSFN informationacquisition instruction (step S409). If the providing method is an MBSFNinformation acquisition instruction, information related to the MBSFNsetting included in the MCCH or the broadcast information is acquired,and information required for receiving the service is acquired (stepS410).

If it is determined at step S409 that the providing method is not anMBSFN information acquisition instruction (or it is a PTP connectioninstruction), the UE1 requests a Bearer for receiving a service bySC-PTP to the eNB3, using an RRCConnectionRequest message of the UL-CCCHor a message of the UL-DCCH (step S411). The eNB3 which has received therequest provides the UE1 with the information required for receiving theservice, using the RRCConnectionSetup message of the DL-CCCH or amessage of the DL-DCCH. The UE1 which has received the message from theeNB3 performs the reception setting based on the information andtransmits a Complete message via the UL-DCCH. The foregoing is thereception setting processing procedure in the UE1.

According to the present embodiment, it becomes possible to provide anappropriate MBMS based on the intra-cell location of the UE1, enablingeffective utilization of radio resources thereby. In addition, since theprocess required in the UE1 only adds to the Counting response a signalbased on reception power of the downlink reference signal which hasalways been being measured and uses it to select a providing method inthe Notification, increase of power consumption can be suppressedwithout requiring a complicated process. In addition, if there are aplurality of UE1s having poor MBMS reception quality, the method of thepatent document 1 cannot optimize the transmission parameters for theUE1 in the vicinity of the cell center because it performs a control tosuppress the number of UE1s having poor reception quality not to exceeda certain value by increasing transmission power of the eNB3. Thecontrol by the present embodiment, on the contrary, can provide optimaltransmission parameters even if there are many UE1s requesting a servicein the vicinity of the cell center.

Although the explanation of the present embodiment has been providedusing a specific RRC message, it is not limited to the using only themessage of the above explanation, provided that its object can beachieved. In addition, although an RB is requested from the UE1 via PTPat step S411 of FIG. 9 in the above explanation, reception setting ofPTP may be performed by the initiative of the base station using amessage such as RRCConnectionReconfiguration from the eNB3 without arequest from the UE1.

Second Embodiment

In the above-mentioned first embodiment, a case has been described wherea signal indicating the intra-cell location is included in the Countingresponse from the UE1. The present embodiment describes a case wherethreshold information related to the intra-cell location of the UE1 isincluded in the Counting so that can request a Counting response to theUE1. The eNB3 and the UE1 of the present embodiment respectively havethe same configurations as those shown in FIGS. 1, 2, 3, and 4 of thefirst embodiment.

Counting and determination of the providing method in the presentembodiment will be described in detail. In the present embodiment,threshold information of the intra-cell location for determining whetheror not the UE1 newly transmits a Counting response is added to theconventional Counting. The threshold information is, for example,information indicating “report when the path loss value is not less thana certain threshold value” and “report when the path loss value is lessthan a certain threshold value” (either “not less than” or “less than”the threshold to be compared). In addition, it is also possible to usereference signal reception power (RSRP) or reference signal receptionquality (RSRQ) instead of the path loss value as described above.

FIG. 10 is a flow chart illustrating an exemplary procedure of theCounting response process in the UE1 according to the second embodimentof the present invention. Upon receiving a Counting signal including thethreshold information, the UE1 determines whether or not the Countingresponse signal generating unit 104 shown in FIG. 1 is requesting aservice based on the service request signal input from the higher layer(step S501). If no service is requested, the flow is terminated. If aservice is requested, the UE1 calculates a path loss value from the basestation transmission power information input from the higher layer andthe result of reception power measurement of the downlink referencesignal held in the measurement information holding unit 103, anddetermines whether or not the station itself transmits a Countingresponse, based on the threshold information included in the Countingsignal (step S502). If it is not assumed to transmit a Countingresponse, the flow is terminated.

If the station itself transmits a Counting response, the UE1 determineswhether or not the station itself transmits a Counting response signal,based on the Probability factor included in MBMS ACCESS INFORMATION(step S503). If it does not transmit a Counting response signal, theflow is terminated. If the station itself transmits a Counting responsesignal, the UE1 inputs the Counting response signal to the transmissionsignal processing unit of the transmitting device shown in FIG. 2 (stepS504). The foregoing is the procedure of the Counting response processin the UE1 in the present embodiment. Here, the NW 601 may notify thethreshold information using the broadcast information instead of theCounting signal. In addition, the NW 601 may notify the thresholdinformation using individual signaling instead of the Counting signal.

Next, a determination procedure of an MBMS providing method in the NW601 receiving the Counting response will be explained. Although thedetermination procedure of the MBMS providing method in the presentembodiment is similar to that in the first embodiment, only the processrelating to acquisition of NumE and NumC is different and thereforeacquisition of NumE and NumC will be explained. Although, in the firstembodiment, NumE and NumC are calculated based on the intra-celllocation information included in the response from the UE1, the presentembodiment first adds the threshold information to the Counting signal,and causes only the UE1 having a path loss value less than a certainthreshold value to respond. NumE can be calculated thereby so that theprocess of step S306 shown in FIG. 8 can be performed. If the process ofstep S307 is required, the procedure causes only the UE1 having a pathloss value not less than a certain threshold value to respond,calculates NumC, and perform the process of step S307. Since receptionsetting of the Notification and the UE1 based on the above determinationis similar to that of the first embodiment, explanation is omittedthereof.

According to the present embodiment, it becomes possible to acquire NumEand NumC for use in determining an MBMS providing method while reducingthe amount of information required for the Counting response, whereby aneffect similar to that with the first embodiment is acquired. Inaddition, it becomes possible to divide the UE1s assumed to transmit aresponse, whereby line congestion at the time of responding can bereduced even if the Probability factor value is set high.

Third Embodiment

In the above-mentioned second embodiment, a case has been describedwhere threshold information of the intra-cell location of the UE1 isincluded so that the NW 601 requests a Counting response to the UE1. Thepresent embodiment describes a case where the NW 601 includes aplurality of different Probability factors in the intra-cell location ofthe UE1. The eNB3 and the UE1 of the present embodiment respectivelyhave the same configurations as those shown in FIGS. 1, 2, 3, and 4 ofthe first embodiment.

Counting and determination of the providing method in the presentembodiment will be described in detail. In the present embodiment, thetypes of Probability factors to be included in MBMS ACCESS INFORMATIONare increased. One is the Probability factor used when the loss value isnot less than a certain threshold value, and one is the Probabilityfactor used when the path loss value is less than a certain thresholdvalue. In addition, the threshold may be included in MBMS ACCESSINFORMATION, or may be preliminarily broadcasted as another message. Inother words, when using two types of Probability factors for the UE1 inidle state and the UE1 in connection state, different Probabilityfactors are respectively set based on the path loss values, resulting ina total of four Probability factors. In addition, it is also possible touse the reference signal reception power (RSRP) instead of the path lossvalue.

FIG. 11 is a flow chart illustrating an exemplary procedure of theCounting response process in the UE1 according to the third embodimentof the present invention. Upon receives a Counting signal including thethreshold information, the UE1 determines whether or not the Countingresponse signal generating unit 104 shown in FIG. 1 is requesting aservice based on the service request signal input from the higher layer(step S601). If no service is requested, the flow is terminated. If aservice is requested and, as a result of comparison between the pathloss value and a predetermined threshold value (step S602), the pathloss value is less than the threshold value, the UE1 sets a codeindicating the vicinity of the cell center as the intra-cell locationinformation, and also sets the Probability factor to a value for thevicinity of the cell center (step S603). If the path loss value is notless than the threshold value, the UE1 sets a code indicating thevicinity of the cell edge as the intra-cell location information, andalso sets the Probability factor to a value for the vicinity of the celledge (step S604).

Next, the UE1 determines whether or not the station itself transmits aCounting response signal, based on the Probability factor selected fromthe path loss values selected at step S603 or step S604 (step S605). Ifit does not transmit, the flow is terminated. If the station itselftransmits a Counting response signal, the UE1 inputs the Countingresponse signal, with the code set at step S603 or step S604 includedtherein, to the transmission signal processing unit 201 of thetransmitting device of FIG. 2 (step S606). The foregoing is theprocedure of the Counting response process in the UE1 in the presentembodiment.

Next, a determination procedure of ad MBMS providing method in the NW601 receiving the Counting response will be explained. Since thedetermination procedure of an MBMS providing method in the presentembodiment differs only in the process relating to acquisition of NumEand NumC similarly to the second embodiment, acquisition of NumE andNumC will be explained. First, setting the two Probability factors inthe present embodiment to the same value provides a similar result tothat of the first embodiment so that NumE and NumC can be acquired.Alternatively, setting one of the two Probability factors to 0, in otherwords, a case where the responding UE1 does not exist in either thevicinity of the cell center or in the vicinity of the cell edge,provides a similar result to that of the second embodiment. However, thepresent embodiment is different in that a code indicating the celllocation information is transmitted in a manner included in the Countingresponse signal, similarly to the first embodiment.

With a setting other than that described above, the Probability factorfor calculating NumE can be gradually raised to reduce the frequency ofrepeating re-Counting by setting the response probability for thevicinity of the cell edge higher than for the vicinity of the cellcenter, and line congestion at the time of responding can be reduced bylowering the response probability for the vicinity of the cell center.If there is no response for the vicinity of the cell center, the numberof UE can be efficiently calculated by adversely lowering the responseprobability for vicinity of the cell edge and raising the responseprobability for the vicinity of the center. According to the presentembodiment, the number of Counting times required for calculating NumCand NumE can be reduced, whereby line congestion at the time ofresponding can be reduced.

The embodiments described above are only illustrative and can beimplemented by a variety of variations and substitutions. Although themobile station and base station of the embodiments have been describedusing functional block diagrams for illustration purposes, control ofthe UE1 and the eNB3 may be performed by recording a program forrealizing the functions of respective parts of the eNB3 and the UE1 or apart of such functions on a computer-readable recording medium, andcausing a computer system to read and execute the program recorded onthe recording medium. The “computer system” mentioned here is assumed toinclude an Operating System and hardware such as peripheral devices.

In addition, the “computer-readable recording medium” refers to aportable medium such as a flexible disk, an Magneto-Optical disk, a ROM,a CD-ROM or the like, or a storage device such as a hard disk built inthe computer system. Furthermore, the “computer-readable recordingmedium” is assumed to include those which hold a program dynamically fora short time such as a communication line when transmitting the programvia a network such as the Internet or a communication line such as aphone line, and those which hold a program for a certain period such asa volatile memory inside a computer system that works as a client and aserver. In addition, the program may be one that realizes a part of theabove-mentioned functions, or one that can realize the above-mentionedfunctions by a combination with a program which has been alreadyrecorded in the computer system.

In addition, each function block used in each embodiment may beimplemented as an LSI which is typically an integrated circuit. Eachfunction block may be individually implemented as a chip, or a part orthe whole of the function block may be integrated into a chip. Inaddition, the technique of fabricating an integrated circuit may berealized by a dedicated circuit or a general-purpose processor withoutbeing limited to an LSI. Additionally, when technology of fabricating anintegrated circuit replacing an LSI appears due to progress ofsemiconductor technology, an integrated circuit based on that technologycan also be used.

Although embodiments of the invention have thus been described in detailabove referring to the drawings, specific configurations are not limitedto the embodiments and designs in a range that does not deviate from thespirit of the invention are included in the appended claims.

REFERENCE NUMERALS

-   -   1 mobile station apparatus (UE)    -   3 eNB    -   100 receiving device    -   104 Counting response signal generating unit    -   200 transmitting device    -   300 receiving device    -   303 Counting response signal aggregating unit    -   400 transmitting device    -   401 transmission signal processing unit    -   402 transmitting unit

1. A wireless communication system including a base station apparatusand mobile station apparatuses to provide an MBMS (Multimedia BroadcastMulticast Service), wherein said base station apparatus transmits amessage for aggregating the number of mobile station apparatusesrequesting an MBMS to a mobile station apparatus being served; and amongsaid mobile station apparatuses, the mobile station apparatus requestingan MBMS adds intra-cell location information of the mobile stationitself to a response message to said message and transmits the responsemessage added with said intra-cell location information to said basestation apparatus.
 2. A wireless communication system including a basestation apparatus and mobile station apparatuses to provide an MBMS(Multimedia Broadcast Multicast Service), wherein said base stationapparatus adds threshold information of intra-cell location of themobile station apparatus to a message for aggregating the number ofmobile station apparatuses requesting an MBMS and transmits the messageadded with said threshold information to the mobile station apparatusbeing served, and among said mobile station apparatuses, the mobilestation apparatus requesting an MBMS determines whether or not torespond to said message based on said threshold information ofintra-cell location and the intra-cell location of its own.
 3. Thewireless communication system according to claim 1, wherein said basestation apparatus receives said response message from said mobilestation apparatus, aggregates the number of mobile station apparatusesrequesting an MBMS for each intra-cell location, and provides an MBMS tosaid mobile station apparatus based on an MBMS providing methoddetermined for said each intra-cell location.
 4. The wirelesscommunication system according to claim 3, wherein said base stationapparatus transmits a message for notifying said MBMS providing methodto a mobile station apparatus requesting an MBMS and, if a plurality ofMBMS providing methods is included in the message for notifying saidMBMS providing method, said mobile station apparatus selects an MBMSproviding method based on intra-cell location information of its own. 5.The wireless communication system according to claim 4, wherein saidMBMS providing method is one of MBSFN (Multicast/Broadcast over SingleFrequency Network), SC-PTP (Single Cell-Point To Point), SC-PTM (SingleCell-Point To Multipoint), and MC-PTM (Multi Cell-Point To Multipoint).6. The wireless communication system according to claim 1, wherein saidintra-cell location information is two-value information indicating thevicinity of cell center and the vicinity of cell edge.
 7. The wirelesscommunication system according to claim 1, wherein said intra-celllocation information is either RSRP (Reference Signal Received Power) ora path-loss value.
 8. A base station apparatus applied to a wirelesscommunication system including a base station apparatus and mobilestation apparatuses to provide an MBMS (Multimedia Broadcast MulticastService), wherein said base station apparatus transmits a message foraggregating the number of mobile station apparatuses requesting an MBMSto a mobile station apparatuse being served, and receives a responsemessage corresponding to said message from said mobile stationapparatus, aggregates the number of mobile station apparatusesrequesting an MBMS for each intra-cell location of said mobile stationapparatus, and provides an MBMS to said mobile station apparatus basedon an MBMS providing method determined for said each intra-celllocation.
 9. The base station apparatus according to claim 8,comprising: a transmission signal processing unit which generates atransmission signal including a message for notifying at least one MBMSproviding method associated with intra-cell location information of amobile station apparatus; and a transmitting unit which transmits saidgenerated transmission signal to said mobile station apparatus.
 10. Amobile station apparatus applied to a wireless communication systemincluding a base station apparatus and mobile station apparatuses toprovide an MBMS (Multimedia Broadcast Multicast Service), wherein saidmobile station apparatus receives from said base station apparatus amessage for aggregating the number of mobile station apparatusesrequesting an MBMS and, when requesting an MBMS, adds intra-celllocation information of its own to a response message to said message totransmit the response message added with said intra-cell locationinformation to said base station apparatus.
 11. The mobile stationapparatus according to claim 10, comprising a counting response signalgenerating unit which, upon receiving a message for aggregating thenumber of mobile station apparatuses requesting an MBMS from said basestation apparatus, adds intra-cell location information of its own to aresponse message corresponding to said message.
 12. The mobile stationapparatus according to claim 10, comprising a counting response signalgenerating unit which, upon receiving a message for aggregating thenumber of mobile station apparatuses requesting an MBMS from said basestation apparatus, determines whether or not to transmit a responsemessage corresponding to said message based on the intra-cell locationinformation of its own.
 13. The mobile station apparatus according toclaim 10, wherein, upon receiving a transmission signal including amessage for notifying at least one MBMS providing method associated withintra-cell location information of a mobile station apparatus from saidbase station apparatus, said mobile station apparatus selects said MBMSproviding method based on the intra-cell location information of itsown.
 14. A communication method of a wireless communication systemincluding a base station apparatus and mobile station apparatuses toprovide an MBMS (Multimedia Broadcast Multicast Service), said methodcomprising at least the steps of: in said base station apparatus,transmitting a message for aggregating the number of mobile stationapparatuses requesting an MBMS to a mobile station apparatus beingserved; and in a mobile station apparatus requesting an MBMS among saidmobile station apparatuses, adding intra-cell location information ofthe mobile station itself to a response message to the message; andtransmitting said response message added with said intra-cell locationinformation to said base station apparatus.
 15. A communication methodof a wireless communication system including a base station apparatusand mobile station apparatuses to provide an MBMS (Multimedia BroadcastMulticast Service), the method comprising at least the steps of: in saidbase station apparatus, adding threshold information of intra-celllocation of a mobile station apparatus to a message for aggregating thenumber of mobile station apparatuses requesting an MBMS; andtransmitting the message added with said threshold information to amobile station apparatus being served; and in a mobile station apparatusrequesting an MBMS among said mobile station apparatuses, determiningwhether or not to respond to said message based on said thresholdinformation of intra-cell location and intra-cell location of the mobilestation itself.